


White Knuckles

by SubwayWolf



Series: Old College Try [6]
Category: It's Always Sunny in Philadelphia
Genre: Anal Training, Dirty Talk, Dom/sub Play, M/M, Pegging, Strap-Ons, Trans Character, Wet & Messy
Language: English
Status: Completed
Published: 2017-08-03
Updated: 2017-08-03
Packaged: 2018-12-10 13:02:01
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,030
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11692182
Author URL: https://archiveofourown.org/users/SubwayWolf/pseuds/SubwayWolf
Summary: Dennis gets his hands on an anal training kit. Charlie is the only viable candidate willing to help him practice.





	White Knuckles

**Author's Note:**

> anon asked: _just a lil suggestion, i'd love to read a charlie/dennis d/s fic where charlie is the dom. i love your series so far!_
> 
> first of all, god bless the person who sent this ask and i hope this lives up to your expectations. also, another person (same person??) sent in a char/den request that involved trans charlie and sub den. how could i say no to that. thanks for your suggestions, and i hope you guys enjoy!!
> 
> i hope you all enjoy this one. in case things are weird or unclear here, dennis is dating mac and wants to train his butt to take mac's dick. sure he's taken dick before but a bit of training never hurt anyone. charlie helps him out. and it's about damn time i wrote trans charlie, right? also, charlie's pov is so fun to write in. so fun, that i had intended this to be 1k at first lmao. enjoy!!!

Dennis kept his gaze fixed on the table, his hands covering the box between them, as if hiding the labelling so they wouldn’t have to read it. As if that would change what was inside.

“I need your help.”

Charlie had to focus hard to keep his jaw from dropping. Dennis Reynolds was being emotionally vulnerable and asking for help? Was he drunk? Did Charlie mishear him? 

“Why would I ever want to help you?” The words came out of Charlie’s mouth before he could stop them. He regretted them immediately.

He half-expected Dennis to go off his hinges and snap, yelling at Charlie for saying that. But instead Dennis lightly shrugged, like he understood. “I don’t know. Maybe you shouldn’t. But this isn’t really for me. This is for Mac.”

“Oh.” Charlie didn’t fully understand what he meant by that but it did succeed in making him less hesitant. “Then… I guess I’ll help.”

“You will!?” Dennis exhaled with relief. “That’s awesome. See, I knew you would help me out, pal. Thank you.”

“Yeah. Whatever. Gimme the box.”

Charlie reached out and pulled the box from under Dennis’ hands. There were words on it, all over, but three big ones on the top. Charlie could make out KIT at the end, and the middle word must have been TRAINING because Dennis said it out loud and Charlie recognized the –ING suffix. Charlie was having trouble making out the first word, which started with an A. The picture on the box showed a woman wearing black underwear with a little plastic purple dildo sticking out the front. Dennis had already explained what that thing, called a strap-on, was used for. So it was pretty obvious the first word had something to do with butts.

Was this going to be like sex? If it was, Charlie didn’t want anything to do with it. But the way Dennis explained it made it seem more like a training process. And if Dennis was trying to get good at this for Mac so they could have sex or whatever, then Charlie could at least try and help. He thought they were a good couple and when they were together, they were a lot calmer and that made the bar run a lot more smoothly and a lot less arguments took place. When Mac and Dennis weren’t on good terms, they took out their frustrations on Dee and Charlie, or they came up with a stupid scheme that got one of them hurt or lost them a lot of money, either way resulting in a hell of a lot of Charlie Work. 

So if Charlie had an opportunity to bring the Dynamic Duo closer together, he would do it. As long as he was absolutely one hundred percent certain this wasn’t sex with Dennis.

“You’re _sure_ this isn’t sex, right?”

“It’s not sex. It’s anal training. It’s like learning something in school, or working out in the gym, or practicing an instrument. You’re like the teacher here, and I’m the student.” Dennis was calm, and most likely not lying. “I promise it’s not sex.”

Charlie stood up and took the training kit with him. “I guess I’ll go put it on, then.”

“Wait.” After a breath, Dennis repeated himself. “Before we do this, I just wanna say thank you, Charlie. This means a lot to me. You’re a great friend.” 

“Whatever, man. I’m just trying to make things easier. For Mac, I mean. Not for you. You just… you make me sad, man. This is sad.” 

Dennis averted his eyes before continuing. “I know you have other things you’d rather be doing right now.” 

“Yeah, no kidding. Frank is down at the bridge as we speak, probably having a crazy good time and finding a lot of cool treasures. But here I am stuck with you. You said it was an emergency.” 

“It is an emergency. And you were the only person I could trust-”

“It’s not an emergency, dude. It’s just pathetic.”

Dennis nodded. Was he… blushing? His ears were red, and his cheeks a shade pinker. If Charlie didn’t know any better, he might assume that meant Dennis liked being degraded. In this context, at least.

Dennis leaned forward in his seat. He made eye contact with Charlie, finally, his eyes blazing. It was so intense that Charlie was compelled to look away and listen to his voice instead.

Dennis’ voice was low. “I’m aware this is an inconvenience to you. So… you can take out your frustrations on me. You can be as mean to me as you want.”

Ah, so it was true. He did like it. 

Charlie nodded. That would be easy, and a lot of fun. He turned and made his way to the bathroom. “I’m going to go put this on so I can train your butt with it. While I’m gone you better not touch yourself… or whatever.”

“What?”

“You heard me, bitch.”

“Not cool. Not sexy, either. Tone it back, dude.”

As Charlie snuck off into the bathroom to change into the strap-on, he made a point to try and focus on coming up with better ways to beat Dennis into submission.

* * *

Everything about this was really sad. When Charlie looked down at the little purple dildo between his legs, he just felt weird about it. Whenever he pictured himself having a dick, he always thought it would be bigger than that, and not purple. The harness looked nothing like it did in the picture on the box – it was less like underwear and more like fabric straps, and they dug into the underside of his asscheeks and were a little tight around his hips. But when he moved, the purple dick moved too, like it was part of him. When he touched it, its base pressed against his clit and it felt kind of good. All in all, the training kit didn’t feel as uncomfortable as he thought it would. It was the situation itself that was unsettling.

Maybe the saddest thing was Dennis. He was on all fours on the bed, completely nude and sticking his ass up. Every few seconds he would look over his shoulder, leaning away in anticipation whenever Charlie got even a little bit close. For a guy who was so insistent and eager at first, he was really cowering up now. 

Dennis had already spread his hole open and greased himself with lube. It looked gross, honestly. It was gaping open and Charlie could see darkness, wetness, and an inhuman shade of pink inside. Were people really turned on by this? For god’s sake – Dennis _pooped_ from there. It was gross and so was Dennis for being excited for it. But even though Charlie didn’t particularly understand sex or pleasure of any kind, that didn’t mean he wouldn’t support his friend’s endeavor, as weird as it was.

It dawned on Charlie that he should probably be telling Dennis all of this. That’s what he wanted, right?

“You are so gross, dude,” Charlie started.

“Fuck you.” Dennis grinded his teeth, so his words came out angry and slightly muffled. “Are you going to put it in or not?”

“You’re not listening to me.” Time to kick it up a notch. Charlie reached up and put a hand in Dennis’ hair, and forced his head down into the mattress, pushing the side of his face against it. “This is so disgusting. You’re naked and sweating all over my bed, and your butt’s in the air like this. It smells like shit, you know that, right?”

Dennis immediately turned a few shades redder. The typical malice and annoyance in his voice vanished. “Sorry.”

Charlie was surprised how well it worked. He kept up the act. “You better be sorry. And you better be really thankful that I’m doing this for you.”

“I am thankful.”

“You owe me, Dennis Reynolds. You have to be nice to me. All week. You have to, uh… you have to do some of my work at the bar.”

“Don’t push it.”

That was fair, Charlie supposed. He realized he was forcing Dennis’ head down kind of hard so he removed his hand. “I’m going to put it in now.”

Dennis laid flat on the bed, face-down on his stomach. He closed his eyes and moved his hands to either side of his head, then grabbed loose fistfuls of the bed sheets.

“Are you ready, man?”

“Put it in, goddamn it.”

Charlie moved his hips forward and watched the tip of the purple dildo disappear slowly into Dennis’ asshole. He was met with some resistance as Dennis tensed up, but he was very slippery and open down there so it wasn’t very difficult. It disappeared down to the base. 

Dennis flushed. He covered his mouth with one hand, trying not to moan or cry out. Charlie unfortunately couldn’t see his face, but could see the muscles of Dennis’ back and shoulders tighten as he tensed up and held his breath, an attempt to even out the pressure and stomach what was undoubtedly a weird sensation. 

“What does it feel like?” Charlie asked, because he was curious. It probably killed the mood, but he genuinely couldn’t tell if Dennis was enjoying this or not.

“It feels – ahh, _fuck_ ,” Dennis whimpered into his hand, his brow knit with tension. “Feels so fucking good. Keep going.”

Charlie tried to remember what people did during sex. He shifted his hips back, pulling the dildo out a bit, then pushed back in. Dennis loosened and tensed again. He released a muffled moan into one hand as the other gripped the bed sheets.

“God damn.” Dennis removed his hand, but his voice was still week and needy, like he was begging. “Don’t stop, Charlie. Do me harder. _Harder_.”

As Charlie kept moving, he grew more and more fascinated with Dennis’ body movements. He got better at relaxing, and it grew easier to push in and pull out. It turned out that he didn’t need much training at all. But the best part about it was the weak, kitten-like noises he was making. He was tense, but his entire body moved and shifted as Charlie pushed in and out. He was warm, almost sweating, but his whole-body tension made it seem like he was going to shatter at any moment.

It made Charlie’s heart pound. Dennis was weak, for once. It would be easy to take control.

Charlie wouldn’t give him real satisfaction until he had some fun first. “Holy shit, look at you. You look and sound like such a bitch right now. You’re crying like a weak little kitten. I am in total control over you. Do you like that, you little bitch?”

Dennis let out a low whine, like a dog getting admonished. He grinded his hips forward in time with Charlie’s, creating friction between his own dick and the bed sheets. 

These insults were definitely helping. It made Charlie feel pretty good, too.

“You’re going to let Mac make you his bitch, too, huh? Are you pretending this is him?”

Dennis moaned again, but it sounded kind of like a sob. His fists were white-knuckled around the sheets. 

“Well, it’s not him right now. It’s me. And you’re lucky I even agreed to this. It’s so pathetic. I mean, you don’t have any other friends? You couldn’t do it yourself because you were too scared? You’re too embarrassed to practice with Mac himself? You think he’ll judge you for being a pussy, huh? You’re so goddamn insecure when it comes to him that you’d rather lie to his face and go behind his back instead. It’s so pathetic and sad.” 

The fucking was so easy now. Charlie’s hips smacked against Dennis’ ass in a gross wet rhythm, creating a sound and scent Charlie would not care to hear ever again. But god damn, putting Dennis in his place like this was worth it. 

Charlie pushed in deep. Surprisingly, it actually got him pretty excited. His head was spinning, his heart was pounding, and he felt hot wetness between his legs, making his black pubes stink, soaking the harness and the places his thighs touched.

Dennis opened up for him, his hole red and gaping as it kept getting pounded. He closed his eyes tightly, and small tears pooled up on his lashes.

Charlie’s hands were practically shaking as he held onto Dennis’ hips. “You’re an asshole, and a bitch, and you can’t even take this dumb little purple dick without crying. What do you have to say for yourself?”

Stubborn as hell even at his weakest, Dennis refused to apologize. He parted his lips and barely forced the words out. “I’m close. I’m gonna come.”

Charlie had forgotten about that. “Ah, gross. Grab a sock or something before you cream all over my goddamn-”

Dennis _moaned_. He had made a lot of noises so far, but none like that. His eyes opened; they were reddened from tears but looked a brighter blue than usual. They were rolling back as he finished all over Charlie’s bed. Dennis shuddered, his hole closing up around the dildo. Charlie pulled back and the dildo popped out of Dennis’ hole with a gross, slick sound. Dennis laid there in bliss, panting.

“Goddamn it. Come on, man! That’s so gross.” They probably should have put down a towel. Not only was there come on Charlie’s sheets, but Dennis sweat so much during sex that the bed was practically soaked at this point.

Dennis rolled over onto his stomach, the still-wet come stain beside him. He said nothing.

Charlie stood up. He was still soaking wet. His thighs stuck together, and his pubes were curling up, damp around the lips of his pussy. He looked around for a clean towel to dry himself up as much as he could. He didn’t want Dennis to notice, but then again, Dennis was in such a blissed-out state that he wasn’t noticing anything.

As Charlie cleaned himself up and took the harness off, he noticed Dennis was being weirdly quiet. Had Charlie been too mean? That couldn’t be possible. Dennis was the best at surviving the Emotional Battery section of Chardee Macdennis, so this was probably child’s play for him. Besides, Charlie wasn’t as mean as he could have been. If he got a little more preparation, he could have thought up some really nasty stuff, but he had been shooting off the cuff here.

“Charlie?”

Charlie, midway through unlatching the harness and taking the dildo out, froze and looked at Dennis, who was now sitting up on the bed.

“Yeah, dude?”

“Thanks. For doing this.”

Charlie furrowed his brow. “You already said that.”

“I know. But I wanted to say it again.” Dennis looked down, at the stain to his right. “I’m going to the dry cleaners tomorrow to drop off some of my shirts, so... I’ll get your sheets done while I’m there. I owe it to you.”

“Oh. That’s cool. Thanks, man.”

Dennis didn’t look at him for a while after that. He got dressed and took the sheets off the mattress. He didn’t berate Charlie or try and make small talk or even say thank you again. He was still weirdly vulnerable. It made Charlie feel guilty, almost.

Once they were both dressed, they looked at each other from across the room, awkwardly catching eyes. Dennis looked away first, but Charlie looked him over. He looked like shit, honestly – hair still wet from sweat, his eyes red, his temperature high. Charlie didn’t blame him for not wanting to shower here, though.

“I was thinking,” Charlie started, grabbing the box off the dresser.

Dennis looked uncomfortable. “Don’t say anything weird or pathetic. Please.”

“No, I wasn’t going to. I was just wondering about the box. Should you take it to your place, or should you leave it here? Because if Frank sees it he’s going to have questions. And I guess you probably don’t want Mac to see it, either.”

“It’s Dee’s kit. I was going to give it back to her.”

“Oh,” Charlie said, and then, with realization, “ _Oh_. Okay. I guess that makes sense. She knows you borrowed it, right?”

“Don’t worry about it.” Dennis walked closer and took the box from Charlie’s hands. He placed it atop the folded sheets he had taken off of the couch and held everything in his arms. He didn’t meet Charlie’s eyes as he did it, and was clearly in a rush to leave. He turned his back and moved towards the door.

Charlie had one last thing to say. “Hey, Dennis. I know I was being mean during that whole… _not_ -sex thing.”

Dennis sighed, and didn’t turn around.

“I wanted to say – really quick and I promise we never ever have to bring it up again – that I don’t think you’re pathetic. I’m glad you’re doing this because obviously it’ll make things easier for you and Mac. And I support that one hundred percent. I support you guys.”

“I know, Charlie.”

“Okay, good.” Charlie fidgeted with his hands, not sure how else to explain himself. “So… just know that I care about you guys. And I did this to help.”

Dennis looked over his shoulder and met eyes with Charlie. “You always try to help. I know that.” His cheeks still burned pink. “We care about you, too. I do. And I trust you. Obviously. Or else I would never have done this.” He didn’t smile, but he was genuine. “Don’t make me say thank you again.

Charlie smiled a little. “Alright. See you at work tomorrow.”

“Goodnight, Charlie.” Dennis opened the door even with his hands full, then stopped one last time before leaving. “Thank you. Again.”

Charlie waved him off, smiling. “Get out of here, bitch.”

Dennis was smiling too as he left and closed the door behind him.

When Frank returned later, he asked where the hell the bed sheets were. But Charlie knew how to keep a secret, and anyway, he fell asleep so fast that he couldn’t answer at all. It was the best sleep he had in a really long time.


End file.
